import { PassThrough } from 'stream'
import got from 'got'
import { StreamType } from '../stream';
import Request from 'got/dist/source/core';
import { video_info } from '..';

export interface FormatInterface{
    url : string;
    targetDurationSec : number;
    maxDvrDurationSec : number
}

export class LiveStreaming{
    type : StreamType
    stream : PassThrough
    private base_url : string
    private url : string
    private interval : number
    private packet_count : number
    private timer : NodeJS.Timer | null
    private video_url : string
    private dash_timer : NodeJS.Timer | null
    private segments_urls : string[]
    private request : Request | null
    constructor(dash_url : string, target_interval : number, video_url : string){
        this.type = StreamType.Arbitrary
        this.url = dash_url
        this.base_url = ''
        this.stream = new PassThrough({ highWaterMark : 10 * 1000 * 1000 })
        this.segments_urls = []
        this.packet_count = 0
        this.request = null
        this.timer = null
        this.video_url = video_url
        this.interval = target_interval * 1000 || 0
        this.dash_timer = setTimeout(() => {
            this.dash_updater()
        }, 1800000)
        this.stream.on('close', () => {
            this.cleanup()
        });
        this.start()
    }
    
    private async dash_updater(){
        let info = await video_info(this.video_url)
        if(info.LiveStreamData.isLive === true && info.LiveStreamData.hlsManifestUrl !== null && info.video_details.durationInSec === '0'){
            this.url = info.LiveStreamData.dashManifestUrl
        }
        this.dash_timer = setTimeout(() => {
            this.dash_updater()
        }, 1800000)
    }

    private async dash_getter(){
        let response = await got(this.url)
        let audioFormat = response.body.split('<AdaptationSet id="0"')[1].split('</AdaptationSet>')[0].split('</Representation>')
        if(audioFormat[audioFormat.length - 1] === '') audioFormat.pop()
        this.base_url = audioFormat[audioFormat.length - 1].split('<BaseURL>')[1].split('</BaseURL>')[0]
        let list = audioFormat[audioFormat.length - 1].split('<SegmentList>')[1].split('</SegmentList>')[0]
        this.segments_urls = list.replace(new RegExp('<SegmentURL media="', 'g'), '').split('"/>')
        if(this.segments_urls[this.segments_urls.length - 1] === '') this.segments_urls.pop()
    }

    private cleanup(){
        clearTimeout(this.timer as NodeJS.Timer)
        clearTimeout(this.dash_timer as NodeJS.Timer)
        this.request?.unpipe(this.stream)
        this.request?.destroy()
        this.dash_timer = null
        this.video_url = ''
        this.request = null
        this.timer = null
        this.url = ''
        this.base_url = ''
        this.segments_urls = []
        this.packet_count = 0
        this.interval = 0
    }

    private async start(){
        if(this.stream.destroyed){
            this.cleanup()
            return
        }
        await this.dash_getter()
        if(this.segments_urls.length > 3) this.segments_urls.splice(0, this.segments_urls.length - 3)
        if(this.packet_count === 0) this.packet_count = Number(this.segments_urls[0].split('sq/')[1].split('/')[0])
        for await (let segment of this.segments_urls){
            if(Number(segment.split('sq/')[1].split('/')[0]) !== this.packet_count){
                continue
            }
            await new Promise((resolve, reject) => {
                let stream = got.stream(this.base_url + segment)
                this.request = stream
                stream.pipe(this.stream, { end : false })
                stream.on('end', () => {
                    this.packet_count++
                    resolve('')
                })
                stream.once('error', (err) => {
                    this.stream.emit('error', err)
                })
            })
        }
        this.timer = setTimeout(() => {
            this.start()
        }, this.interval)
    }
}

export class Stream {
    type : StreamType
    stream : PassThrough
    private url : string
    private bytes_count : number;
    private per_sec_bytes : number;
    private content_length : number
    private request : Request | null
    constructor(url : string, type : StreamType, duration : number, contentLength : number){
        this.url = url
        this.type = type
        this.stream = new PassThrough({ highWaterMark : 10 * 1000 * 1000 })
        this.bytes_count = 0
        this.per_sec_bytes = Math.ceil(contentLength / duration)
        this.content_length = contentLength
        this.request = null
        this.stream.on('close', () => {
            this.cleanup()
        })
        this.loop()
    }

    private cleanup(){
        this.request?.unpipe(this.stream)
        this.request?.destroy()
        this.request = null
        this.url = ''
        this.bytes_count = 0
        this.per_sec_bytes = 0
    }

    private loop(){
        if(this.stream.destroyed){
            this.cleanup()
            return
        }
        let end : number = this.bytes_count + this.per_sec_bytes * 300;
        let stream = got.stream(this.url, {
            headers : {
                "range" : `bytes=${this.bytes_count}-${end >= this.content_length ? '' : end}`
            }
        })
        this.request = stream
        stream.pipe(this.stream, { end : false })

        stream.once('error', (err) => {
            this.stream.emit('error', err)
        })

        stream.on('data', (chunk: any) => {
            this.bytes_count += chunk.length
        })

        stream.on('end', () => {
            if(end < this.content_length) this.loop()
            else this.cleanup()
        })
    }
}